Method of pointing and threading screws, bolts, and similar articles.



y R. L. WILCOX. METHOD OF POINTING AND THREADING SCREWS, BOLTS, ANDSIMILAR ARTICLES.

APPLICATION FILED JULY-21. 191s. 1,249,874. Patented Dean, 191?. Em1

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htlf'UI-IAI-tl) LESTER WILCOX, OF WATERBURY, CONNECTICUT, ASSIGNOR TOTHEWATER- BURY FARREL FOUNDRY AND MACHINE COMPANY, OF WATERBURY,CONNECTICUT,

a eonronarron or connno'rroor.

ME llI-IUIU F POlfNTING AND THREADING SCREWS, BOLTS, ANI} SIMILARARTICLES.

Specification of Letters Patent, Patented [bee 11, 1911 llriginalapplication filed August 23, 1915, Serial No. 46,940. Divided and thisapplication filed July 21,

1916. Serial No. 110,517.

To all whom it may concern:

lie it known that I, RICHARD LESTER WILcoX, a citizen of the United.States, residing; at VVaterbur-y, in the county of New Haven and StateofConnecticut, have 1nvented a certain new and Improved Method forPointing and Threading Screws, Bolts,

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'llti and Similar Articles, ofwhich the following is a specification,reference being had thereln to the accompanying drawings.

My invention relates to a new and improved method for pointing andthreading screws, bolts and similar articles, preferably with dies. Tothese, and other ends, my invention consists in the method for pointingand thread i119; screws, bolts and similar articles, substantially ashereinafter described and illustrated in the accompanying drawing,wherein,-- y y c Figure 1 is a plan view of a pair of thread rollingdies which may be used in my improved process; a y y y Fin. 2 is aperspective view of one of such dies;

Fig. 3 depth gage removed;

Fig. l is an end view. thereof;

Fig. 5 is a face view ofthedenth gage;

Fig. 6 is an edge view thereof;

Figs. 7, 8, 9, 10 and 11 are enlargedsectional views of the die anddepth gage, taken respectively upon linesA, B, C, D and E of figure 3,with the blankshown in connection therewith; and

F 1g. 12 1s a fragmentary plan now .of one.

of the dies and depth gage with the blank in contact therewith.

Heretofore gimlet. point screws have generally been produced by firstpointing the blank in a shaving machine, lathe or snnilar mechanism andafterward forming the thread thereon or by rolling a V groove is a faceview thereof withthe eachother during this movement,

timeand without the loss of any material, as is necessary under theol dpractice.

One form of means for practising" my improved process is shown in thedrawings,

wherein the numeral 2 designates the fixed die and 1 the movable die,both being of substantially the same shape, differing only in theirlength, the movable die being longer than the fixed die and providednotch 3.

with a guide These diesare secured in theusual way in any one of thecommon forms of thread rolling machine. Each die has an angle recess iin one side thereof at an angle to the top and bottom and upon theadjacent faces are the ribs 5, which are parallel to the side of thedies andterininate at their inner ends at the edge of therecess 4.

The front face of each of the dies is provided with the usual threadrolling grooves 6, which extend from the outer edges of the i blank asthe end thereof passes over it.

The dies 1 and 2 are so arranged that the In practice, the cloak, headedat only one end, designated herein by the numeral 10, is placed betweenthe dies in the usual manner, with the bottom end thereof resting uponthe contact face 11 of the lip 9, its alinement being determined by theguide notch 3, and its then position being substantially shown in Fig.12. The guide notch 3 is not essential to the operation of the devicebut is eommon in thread rolling dies.

As the movable die 1 advances parallel with the face of the fixed die 2,the thread is rolled upon the shank of the blank from lip 9 is slightlycurved .to allow for the elongation of the the head down to a point nearthe bottom thereof, there being grooves 6 at this point to form thethreads (see Figs. 7 and 8). As

the threads are rolled, the blank is slightly elongated by stretchingtoward its bottom end, the engagement of the rolled threads and grooves6 preventing elongation in the opposite direction, until the threads aresubstantially completed and the blank is at that part of the diesubstantially designated by the line C in Fig. 3 and as illustrated inFig. 9. At about this time the lower end of the blank is brought intocontact with the ribs 5 and the elongated portion thereof is tapered byreason of its Contact therewith and is" ointcdsubstantially as shown'inFig. 11. uri'ng this pointing operation the grooves in the side of theribs 5 roll the thread on the screw until the completed blank is formedat that portion of the die substantially illustrated by line E in Fig.8, and in Fig. 11. I

The blank is only supported by the lip 9 of the depth gage 8 until suchtime as the threads on the shank are of suflicient depth to insure theproper alinement of the blank in the die, and after this has beenaccomplished, the'blank passes beyond the lip 9, as shown in Fig. 9, andthere is nothing to retard the elongating action of the blank throughthe thread rolling operation. This elongation of the blank continueswhile the thread is being rolled on the pointed portion,thusfacilitating the pointing operation.

If the metal in the blank is of such a nature that it will not flow byreason of the thread rolling operation, the blank is placed between thedies for substantially its full length, instead of slightly shorter, asis the case with the blank composed of metal capable of flowing freely.

It will be observed that in the embodiment of 'my invention, as hereindescribed, gimlet pointed screws .or bolts are pointed and threadedwithout waste of material, and the old pointing operation whereinmaterial is wasted is eliminated.

In minor details the means adopted to accomplish my new and improvedmethod maybe altered'and I do not therefore limit myself to detailsthereof constructed exactly as shown and described, except as the scopeof the claims requires.

Having described my ilivelitioinavliat I claim as new and desire tosecure by Letters Patent, is:

1. A method of manufacturing articles as described, consisting in firstrolling a thread on a portion of a blank and then progressivelyadvancing the thread toward one end of the blank, elongating the blanktoward the same end and tapering the elongated portion.

2. A method of manufacturing articles as described, consisting in firstrolling a thread on 'a portion of a blank and then pregressivelyadvancing the thread toward one end of the blank, elongating the blanktoward the same end, tapering the elongated portion and finally forminga thread on the tapered elongated portion.

In a method of manufacturing articles as described, the use of dieswhich operate first to roll a thread on a portion of a blank and thenprogressively advance the thread toward one end of the blank, elongatingthe blank toward the same end, tapering the elongated portion andfinally forming a thread on the tapered elongated portion.

4. In a method of manufacturing articles as described, the use of diesprovided with a depth gage for a blank and operating to first roll athread on a portion of the blank and then progressively advancing thethread to the end of the blank.

5. In a method of manufacturingarticles as described, the use of diesprovided with an adjustable depth gage for a blank and operating tofirst roll a thread on a portion of the blank and then progressivelyadvancing the thread to the end of the blank.

6. The process of pointing a blank and rolling a thread thereon withoutwaste of material, which consists in rolling a thread upon a portion ofthe shank, which is elongated thereby, and then pointing and rolling athread upon said elongated portion.

In testimony whereof I have hereunto affixed my signature.

RICHARD LESTER VVILCOX.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents,

' Washington, D. C.

